In 1846 and 1847 Mr. Walter Mantell, eldest son of Dr. Mantell, who had resided several years in New Zealand, explored every known locality within his reach in the North Island. He also went into the interior of the country and lived among the natives for the purpose of collecting specimens, and of ascertaining whether any of these gigantic birds were still in existence; resolving, if there appeared to be the least chance of success, to penetrate into the unfrequented regions, and obtain a live Moa. The information gathered from the natives offered no encouragement to follow up the pursuit, but tended to confirm the idea that this race of colossal bipeds was extinct. He succeeded, however, in obtaining a most interesting collection of the bones of Moa-birds, belonging to birds of various species and genera, differing considerably in size. This collection was purchased by the trustees of the British Museum for £200. Another collection was made by Mr. Percy Earle from a submerged swamp, visible only at low water, situated on the south-eastern shore of the Middle Island. This collection also was purchased by the trustees for the sum of £130. Mr. Walter Mantell, who described this locality, near Waikouaiti, seventeen miles north of Otago, thinks it was originally a swamp or morass, in which the New Zealand flax once grew luxuriantly. The appearance and position of the bones are similar to those of the quadrupeds embedded in peat-bogs, as, for instance, the great Irish elk (see next chapter). They have acquired a rich umber colour, and their texture is firm and tough. They still contain a large proportion of animal matter. Unfortunately, even when Mr. Walter Mantell visited this spot, the bed containing the bones was rapidly diminishing from the inroads of the sea, and perhaps by this time is entirely washed away. Mr. W. Mantell, however, obtained fine specimens and feet of a large Moa-bird (Dinornis) in an upright position; and there seems to be little doubt that the unfortunate bird was mired in the swamp, and perished on the spot. The bones which he obtained from the North Island presented a different appearance, being light and porous, and of a delicate fawn-colour. They were embedded in loose volcanic sand. Though perfect, they were as soft and plastic as putty, and required most careful handling. They were dug out with great care, and exposed to the air and sun to dry before they could be packed up and removed. The natives were a great source of trouble to him, for as soon as they caught sight of his operations they came down in swarms--men, women, and children, trampling on the bones he had laid out to dry, and seizing on every morsel they could get. The reason of this was that their cupidity and avarice had been excited by the large rewards given by Europeans in search of these treasures. Mixed with the bones he found fragments of shells, and sometimes portions of the windpipe, or trachea.